ControlDesigner

@Bradley: thanks for pointing me in the right direction

You will need to write a ControlDesigner class, then use it in a [Designer( ... )] attribute on your UserControl.

See the example here: http://msdn.microsoft.com/en-us/library/sycctd1z(v=VS.90).aspx

For the actual click:

http://msdn.microsoft.com/en-us/library/system.windows.forms.design.controldesigner.gethittest(v=VS.90).aspx

The ControlDesigner has a protected bool GetHitTest(Point point) method - you can implement this in your ControlDesigner and return true when you want your control to handle a click, based on the click‘s location on the screen.

相关资料

http://www.cnblogs.com/blueglass/archive/2012/06/01/2530030.html